1. Field of the Invention
The invention relates to a method for operating a hybrid vehicle having an internal combustion engine and an electric machine, and having a regenerable filter device that absorbs fuel vapors from a fuel tank of the internal combustion engine.
2. Description of the Related Art
German laid-open patent application DE 10 2007 002 188 A1 discloses a hybrid vehicle having an electric motor and an internal combustion engine. The internal combustion engine does not run continuously, but instead is switched off when a drive is provided purely by electric motor. Hydrocarbons scavenged from a filter device into an intake section cannot be burned in the switched-off state. A control device of the known hybrid vehicle switches on the internal combustion engine in an electric operating mode of the hybrid vehicle as a function of a charge state of the filter device. As a result, hydrocarbons scavenged into the intake section can be fed from the filter material to combustion.
The object of the invention is to improve the reproducible operation of a hybrid vehicle having an internal combustion engine and an electric machine and having a regenerable filter device that absorbs fuel vapors from a fuel tank of the internal combustion engine, in particular in a specific test operating mode.